Online banking ... my loss was also my gain!

I lost money when making an online payment to my mum's MasterCard (Online banking loophole risk, Cash, last week). I put in the correct card number but the wrong sort code, so £350 went to someone else's M&S MasterCard. I didn't realise that two MasterCards could have the exact same number, but there you go.

My bank, though sympathetic, said it couldn't do anything because it was my error. I couldn't agree with them more; it was completely my own fault, and so have learned to live with losing a small, but not insignificant, sum and will definitely check all card details before ever making any sort of payment again. In the meantime, one dishonest M&S MasterCard holder will no doubt have enjoyed spending the cash on their credit card.H, by email

Here in Germany I once found cash in my account and my bank rang me pretty smartish to check that it was a mistake (payment for a used car) and revoked the transaction, sending it back to the payer. Simple.mseymour, guardian.co.uk/money

First Direct does not allow you to delete payees and they take 13 months to drop off from the last payment. I made a payment to a company's old account and it took two months to get a refund.

They denied having received it or having access to it, but the account trace said it was still active. I got my £41 back because FD paid me, but if a company/individual ignores its requests, it looks like you can't do anything.Halo572, guardian.co.uk/money

Nothing is ever our fault these days, is it? If we ever do anything wrong, someone else should jolly well incur the time and cost of sorting it out. I live in a country where the sending of electronic payment is normal. It is a leap of faith when you send the payment ... but that's an inherent risk. Therefore, it seems entirely reasonable that if I want to use this process, the onus is on me to get the recipient's information right. oommph, guardian.co.uk/money

Making sure you're the winner in a split decision, Cash, last week, is a headline that explains, in a nutshell, why people, especially men, wish to protect their assets by not marrying. Living under the same roof should not give you an automatic right to wealth someone else has built up. If someone doesn't want to marry you and you don't like that, you can draw the appropriate conclusion.Persianwar, guardian.co.uk/money

My partner and I are in the process of buying our first house. I have always been aware that, as a couple living together, we would have no legal claim on each other's assets in the event of death or a break-up. As a result we are putting in place measures to cover ourselves. This is particularly important for my partner who has four children.

We have been upfront about this. We have a joint tenancy, wills, statements of wish for our pension and life assurance and we are putting in place a cohabitation agreement. But a friend's partner refuses to address these issues. Like so many others, she thought she had rights under "common law".NW, by email

People living together are particularly vulnerable if there is no will. And yet research by Will Aid reveals that among couples living together, not having a will could be the norm. In November, instead of charging its usual fee, Will Aid solicitors will write basic wills and ask for a donation to Will Aid' charities. Last year's campaign raised almost £1m and £5.4m in legacies.Sue Davison, Will Aid, by email

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